MAC Layer Performance of Different Channel Estimation Techniques in UTRAN LTE Downlink

Long Term Evolution (LTE) is the new standard proposed by the 3GPP to evolve towards 4G. Evolved UTRAN (E-UTRAN) specifications are currently completed and research groups are studying the performance of the last Release 8. Nevertheless, these studies lack a full modeling of the MAC layer because they either leave out retransmissions and turbo coding or assume ideal channel estimation. This paper uses an accurate LTE MAC layer simulator to perform a complete downlink LTE performance study. Results compare different channel estimation techniques showing significant difference among them, most of all regarding the robustness of the estimator against errors. Finally, LTE system performance assessment is presented employing a realistic channel estimator.